310
FXAK69 PAFG 192126
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
126 PM AKDT Sun May 19 2024

.SYNOPSIS...
Scattered showers and isolated afternoon thunderstorms are
expected to develop along the thermal trough today. Increased
moisture and upper level energy moving across the eastern Alaska
Range and the southeastern Interior tonight into Monday will bring
the potential for heavy showers; at higher elevations accumulating
snow is possible. A weather front moves to the West Coast and
Western Interior tonight into Tuesday, bringing showers and
increased southeasterly winds. The front moves into the central
Interior by late Tuesday. Flood Warning remains in place for the
Yukon River at Pilot Station.

&&

.DISCUSSION...
Synoptic Analysis and Forecast...
Aloft, at 500 mb, a 534 dam low is over the northern Gulf of Alaska,
a 542 dam low is southeast of Inuvik, a 534 dam low is over the
Gulf of Anadyr, and a 527 dam low is between the southern
Kamchatka Peninsula and Shemya. The low over the northern Gulf of
Alaska slides east to be near Yakutat by Monday morning and east
into northern British Columbia through Tuesday. As this low moves
east, the low near Inuvik gets pushed northward to Banks Island by
Tuesday. The low near the Gulf of Anadyr tracks southwest through
Monday, while the low east of the Kamchatka Peninsula tracks
east, with the lows merging over the Western Bering northwest of
the Pribilofs Monday night. This new low lifts northeast towards
the Y-K Delta through Tuesday. Between the low in the Bering and
the low in British Columbia, weak ridging develops across central
and eastern Alaska.

At the surface, a 1009 mb low near Noatak moves northwest to be 25 NM
northwest of Kivalina by Monday morning, weakening to 1013 mb
Monday afternoon as it moves to be 75 NM west of Point Hope,
dissipating Monday night. A 1009 mb low is east of Northway this
afternoon with a thermal trough extending northwest across the
Middle Tanana Valley to the Lower Koyukuk Valley. The low east of
Northway moves north to be between Northway and Eagle by Monday
morning, weakening through the day. A 1012 mb low moves north off
of the Northwest Territory coast Monday afternoon and over Banks
Island late Tuesday morning. High pressure remains over the Arctic
water with a 1025 high developing and becoming centered 400 NM
north of Utqiagvik by Tuesday afternoon. A 993 mb low in the far
western Bering Sea this afternoon tracks northeast to be 350 NM
northwest of the Pribilofs by Monday morning, 250 NM northwest of
the Pribilofs by Monday afternoon, and a 150 NM east of the
Pribilofs by Tuesday afternoon. As this low tracks east northeast
it will push a front towards the West Coast Monday afternoon,
moving onshore the Y-K Delta and St Lawrence Island during the
evening and overnight hours and pushing northeast across the
Seward Peninsula and Western Interior Tuesday.

Models...
The 19/12Z models initialized well against the 12Z RAOBS and are in
good agreement with the overall synoptic pattern through Monday.
There are some minor differences in the timing of weak impulse
moving through the trough, but the impacts of the differences are
very minimal. Continued the trend of leaning towards the NAM and
hi-res models for winds and a general blend for QPF and pops.
Overall made very few edits to the inherited forecast package.

North Slope and Brooks Range...
Fairly quiet across the North Slope and Brooks Range over the next
several days. High pressure over the Arctic will maintain areas
of stratus and periods of fog, as well east northeast winds of 10
to 20 mph range along the coast. Southerly winds develops Tuesday
in the eastern Brooks Range, resulting in warming temperatures in
the eastern Brooks Range and central and western Arctic Plains.

West Coast and Western Interior...
Quiet through Monday afternoon, with only a few spotty showers
expected. A weather front pushes over the Y-K Delta and St
Lawrence Island late Monday and then moves northeast across the
Seward Peninsula and Western Interior through Tuesday. East to
southeast winds of 15 to 25 mph are expected with the front, with
the strongest winds along the coast. Precip chances increase with
the approach and passage of the front. Most precip will fall as
rain with some snow over the Bering coastal regions.

Central and Eastern Interior...
Scattered afternoon showers and isolated thunderstorms (mainly over
the Fortymile Country) expected across the Interior today along
the thermal trough. Upper level low moving out of the Gulf of
Alaska and into northern British Columbia tonight into Monday
pushes moisture across the Eastern Alaska Range and the southeast
Interior, bringing increased chances for heavy showers, especially
over the eastern Alaska Range. Rainfall amounts of half an inch
to as much as an inch are possible in the eastern Alaska Range
tonight through Monday night. From Delta Junction to Dot Lake up
to half an inch of rain is possible. A mix of rain and snow is
possible tonight into early Monday morning in locations such as
Tok and Robertson River. Accumulating snow is possible in
elevations above 2500 to 3000 feet, especially in upslope areas of
the Alaska Range where 4 to 6 inches are possible. A front moving
Tuesday will bring some showers to the Interior as well as
increasing southerly gap winds in the Alaska Range. A Wind
Advisory may be needed for Isabel Pass Tuesday night into
Wednesday, as wind gusts may approach 50 mph.

Extended Forecast Days 4-7...Deterministic and ensemble means
continue to indicate a series of upper level lows in the Bering
that squash the eastern Pacific Ridge. This will likely maintain
continued chances for showers across the Interior and West coast
through the week. Temperatures cool slightly for the latter half
of the week.

Coastal Hazard Potential Days 3 and 4...None.

&&

.FIRE WEATHER...
Scattered showers are expected into early next week across the
Interior. Thunderstorm potential continues through today along the
thermal trough, with the best chances occurring over the Fortymile
Country. Wetting rains develop tonight into Monday over the
southeastern Interior and eastern Alaska Range. Southerly gap flow
develops Tuesday into Wednesday om the Alaska Range passes with
gusts to near 50 mph overnight Tuesday into Wednesday.

&&

.HYDROLOGY...
A flood warning is out for the Yukon River near Pilot Station due
to an ice jam, and a flood watch for the Yukon River to St.
Mary`s. Concern will likely continue downstream for ice jams as
ice remains thick. Water is also backing up along the Buckland
River due an ice jam upstream of Buckland. This area will be
monitored for possible flooding. Elsewhere, there will be up to an
inch of rainfall (mixed snow above 2500 feet) over the E Alaska
Range late this afternoon through Monday afternoon. No concerns at
this time for this rainfall and snowfall.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Flood Watch for AKZ826.
PK...Brisk Wind Advisory for PKZ811.
     Brisk Wind Advisory for PKZ812.
     Brisk Wind Advisory for PKZ815-861.
     Brisk Wind Advisory for PKZ857.
     Brisk Wind Advisory for PKZ858.
&&

$$